Organic compounds having a perfluoroalkyl group are important intermediates of organic electronic materials, medicine, agricultural chemicals, functional polymer materials and the like. Many synthetic examples have been reported of trifluoromethyl compounds among others.
The Ruppert-Prakash reagent (trifluoromethyltrimethylsilane, CF3SiMe3) is known as a trifluoromethyl source used in the trifluoromethylation reaction of organic compounds, and it has been reported that a reaction with the following organic compounds provides a corresponding trifluoromethyl compound: aldehyde (Non-Patent Document 2, Non-Patent Document 3, Non-Patent Document 4, Non-Patent Document 5), ketone (Non-Patent Document 1, Non-Patent Document 2, Non-Patent Document 3, Non-Patent Document 4, Non-Patent Document 5), ester (Non-Patent Document 2, Non-Patent Document 3, Non-Patent Document 5), lactone (Non-Patent Document 2), acid halide (Non-Patent Document 2), amide (Non-Patent Document 2, Non-Patent Document 3), imide (Non-Patent Document 2), aziridine (Non-Patent Document 2), alkyl halide (Non-Patent Document 2), aryl halide (Non-Patent Document 2), sulfur compounds (Non-Patent Document 2), organic metal compounds (Non-Patent Document 2), nitroso compounds (Non-Patent Document 2), phosphorus compounds (Non-Patent Document 2, Non-Patent Document 3), imine (Non-Patent Document 3), porphyrin (Non-Patent Document 3), arylsulfonyl fluoride (Non-Patent Document 6), etc. It is however undeniable that the high cost of trifluoromethyltrimethylsilane presents a barrier to mass production.
Meanwhile, trifluoromethane is a material with a potential of being a trifluoromethyl source, since it is industrially mass produced as a byproduct in the Teflon (Registered Trademark) production process, so that it may be obtained in a large quantity at a low cost. There have been reported examples of Synthesizing trifluoromethyl compounds that correspond to the following materials by using trifluoromethane in a reaction with those materials: aldehyde (Non-Patent Document 7, Non-Patent Document 8, Non-Patent Document 10, Non-Patent Document 11, Non-Patent Document 12, Non-Patent Document 13, Non-Patent Document 14, Patent Document 3, Patent Document 4), ketone (Non-Patent Document 7, Non-Patent Document 9, Non-Patent Document 11, Non-Patent Document 13, Non-Patent Document 14, Non-Patent Document 15, Patent Document 1, Patent Document 2, Patent Document 4), ester (Non-Patent Document 7, Non-Patent Document 13, Patent Document 4), acid halide (Non-Patent Document 7, Non-Patent Document 13), boron compound (Non-Patent Document 7, Patent Document 4), silicon compound (Non-Patent Document 7, Patent Document 4), elemental sulfur (Non-Patent Document 7, Patent Document 4), disulfide (Non-Patent Document 14), epoxide (Non-Patent Document 13), carbon dioxide (Non-Patent Document 13, Patent Document 4), alkyl halide (Patent Document 4), aryl halide (Patent Document 4), arylsulfonyl fluoride (Non-Patent Document 15), etc. However, trifluoromethane has a low boiling point (−83° C.) and a low reactivity due to low acidity (pKa=27), so the activation of trifluoromethane requires a strong base, such as a base generated by an electrochemical method (Non-Patent Document 11, Non-Patent Document 12), phosphazene base (Non-Patent Document 13, Non-Patent Document 14, Non-Patent Document 15, Patent Document 3), potassium tert-butoxide (Non-Patent Document 9), potassium hexamethyl disilazide (Non-Patent Document 8, Non-Patent Document 9, Patent Document 1, Patent Document 2, Patent Document 4), sodium hydride (Non-Patent Document 9), potassium dimsylate (Non-Patent Document 8, Non-Patent Document 10). These strong bases are costly, and at the present stage, they are not necessarily good for application to industrial mass production. There is also a report that reaction proceeds by using a catalytic amount of base (Non-Patent Document 15), but the substrate is limited, and the method is not generally applicable.
Meanwhile, no synthetic example other than trifluoromethane which uses RFH (monohydroperfluoroalkane) represented by General Formula [3] has been reported so far.